# Clinical Cases: Pericardial Disease

## Case 1: Acute Pericarditis - Classic Presentation

### Clinical Image
![Pericarditis ECG](case_01_image.jpg)
*Source: [Wikimedia Commons - Pericarditis ECG](https://commons.wikimedia.org/wiki/File:Pericarditis_ECG.svg) - CC BY-SA 3.0*

### Patient Presentation
A 24-year-old man presents to the emergency department with sharp chest pain that began yesterday. The pain is worse when he lies flat and when he takes a deep breath, and improves when he sits up and leans forward. He had a "cold" with fever, sore throat, and myalgias about 10 days ago that has since resolved. He has no significant medical history and takes no medications.

### Demographics
- Age: 24 years
- Sex: Male
- Past Medical History: None
- Medications: None
- Social History: College student, no smoking, occasional alcohol

### Chief Complaint
Sharp chest pain worse with inspiration and lying flat, better with sitting forward

### Physical Examination
- Temperature: 37.8°C (low-grade fever)
- Blood pressure: 118/74 mmHg
- Heart rate: 92 bpm
- Respiratory rate: 18/min
- Oxygen saturation: 99% on room air
- General: Appears uncomfortable, sitting forward
- Cardiovascular: Three-component pericardial friction rub best heard at left lower sternal border with patient leaning forward at end-expiration
- Respiratory: Clear to auscultation
- No JVD, no peripheral edema

### Workup
- ECG: Diffuse ST elevation with upward concavity ("saddle-shaped"), PR depression in leads II, III, aVF and V2-V6; PR elevation in aVR
- Troponin: 0.08 ng/mL (mildly elevated - myopericarditis)
- CRP: 8.2 mg/dL (elevated)
- ESR: 45 mm/hr (elevated)
- WBC: 11,200/μL
- Echocardiography: Small circumferential pericardial effusion (5 mm), normal LV function
- Chest X-ray: Normal cardiac silhouette

### Diagnosis
Acute Viral/Idiopathic Pericarditis with Mild Myopericarditis

### Treatment
1. **NSAIDs** (ibuprofen 600 mg TID or aspirin 750-1000 mg TID) for 1-2 weeks
2. **Colchicine** 0.5 mg BID for 3 months (reduces recurrence by ~50%)
3. Activity restriction until symptoms resolve and inflammatory markers normalize
4. Gastric protection with PPI during NSAID therapy
5. Avoid corticosteroids (increase recurrence risk)
6. Follow-up echocardiogram if symptoms persist
7. Return precautions for worsening symptoms, dyspnea, or syncope

### Physiological Principles Demonstrated
- **Pericardial pain characteristics**: Pain is pleuritic (worse with inspiration) because the inflamed pericardium moves with respiration. Improvement with leaning forward reduces pericardial stretch.
- **Friction rub mechanism**: The three-component rub corresponds to atrial systole, ventricular systole, and early ventricular diastole when inflamed pericardial layers rub against each other.
- **ECG evolution**: Stage 1 (diffuse ST elevation, PR depression) reflects epicardial inflammation. Unlike STEMI, changes are diffuse and do not follow coronary territories.
- **Viral etiology predominance**: In developed countries, most cases are idiopathic or presumed viral; extensive workup is not indicated in uncomplicated first presentations.

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## Case 2: Cardiac Tamponade - Hemodynamic Emergency

### Clinical Image
![Cardiac Tamponade Echo](case_01_image.jpg)
*Source: [Wikimedia Commons - Pericardial effusion](https://commons.wikimedia.org/wiki/File:Pericarditisultrasound.png) - CC BY-SA 3.0*

### Patient Presentation
A 58-year-old woman with metastatic breast cancer presents with progressive shortness of breath and lightheadedness over the past week. She notes that her symptoms are worse when lying flat and she has had to sleep propped up on pillows. Today she nearly fainted when standing up from bed. She completed chemotherapy 2 months ago.

### Demographics
- Age: 58 years
- Sex: Female
- Past Medical History: Metastatic breast cancer to bone and liver, treated with chemotherapy
- Medications: Tamoxifen, analgesics for bone pain
- Family History: Mother with breast cancer

### Chief Complaint
Progressive dyspnea, orthopnea, and near-syncope

### Physical Examination
- Blood pressure: 88/72 mmHg (narrowed pulse pressure)
- Heart rate: 112 bpm
- Respiratory rate: 24/min
- Oxygen saturation: 94% on room air
- Pulsus paradoxus: 18 mmHg (>10 mmHg is abnormal)
- General: Appears ill, anxious, sitting upright
- Neck: JVP elevated to angle of jaw, does not fall with inspiration (Kussmaul sign absent - more typical of constriction)
- Cardiovascular: Distant, muffled heart sounds; tachycardic, regular rhythm
- Extremities: Cool, clammy

### Workup
- ECG: Sinus tachycardia, low voltage QRS, electrical alternans (beat-to-beat variation in QRS amplitude)
- Chest X-ray: Enlarged cardiac silhouette ("water bottle" shape), clear lung fields
- Echocardiography:
  - Large circumferential pericardial effusion
  - Right atrial collapse during late diastole
  - Right ventricular diastolic collapse
  - Dilated IVC without respiratory variation (plethora)
  - Respiratory variation in mitral and tricuspid inflow velocities >25%
- BNP: Mildly elevated (250 pg/mL)

### Diagnosis
Cardiac Tamponade due to Malignant Pericardial Effusion

### Treatment
1. **Urgent pericardiocentesis** under echocardiographic guidance
   - Removed 650 mL of bloody pericardial fluid
   - Immediate hemodynamic improvement
2. Fluid cytology sent: Positive for malignant cells (adenocarcinoma consistent with breast primary)
3. Consider pericardial drain catheter placement to prevent reaccumulation
4. Options for recurrence prevention:
   - Pericardial window (surgical)
   - Intrapericardial sclerotherapy
   - Systemic cancer treatment
5. Oncology consultation for goals of care
6. Avoid diuretics and vasodilators (reduce preload, worsen tamponade)

### Physiological Principles Demonstrated
- **Beck's triad**: Hypotension, elevated JVP, and muffled heart sounds (present in this case) - indicates acute tamponade with hemodynamic compromise.
- **Pulsus paradoxus mechanism**: In tamponade, ventricular interdependence is exaggerated. Inspiration increases RV filling at the expense of LV filling (septum shifts left), causing >10 mmHg drop in systolic BP.
- **Chamber collapse sequence**: Right-sided chambers collapse first because pressures are lower. RA collapse occurs in late diastole/early systole; RV collapse occurs in early diastole.
- **Acute vs. chronic effusion**: This large effusion caused tamponade because it accumulated relatively rapidly. Slowly accumulating effusions allow pericardial stretch and may exceed 1 liter without hemodynamic compromise.

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## Case 3: Constrictive Pericarditis - Diastolic Filling Impairment

### Clinical Image
![Constrictive Pericarditis CT](case_01_image.jpg)
*Source: [Radiopaedia - Pericardial calcification](https://radiopaedia.org/articles/constrictive-pericarditis) - Educational use*

### Patient Presentation
A 62-year-old man presents with progressive lower extremity edema, abdominal swelling, and fatigue over the past 6 months. He was treated for tuberculous pericarditis 20 years ago in his home country before immigrating. He denies chest pain or dyspnea at rest, though he becomes short of breath with exertion. He has noticed his legs swell by the end of the day, and his wife says his abdomen has been getting bigger.

### Demographics
- Age: 62 years
- Sex: Male
- Past Medical History: Tuberculous pericarditis (treated 20 years ago), latent TB
- Medications: None currently
- Social History: Born in Philippines, immigrated 15 years ago

### Chief Complaint
Progressive edema, abdominal distension, and exercise intolerance

### Physical Examination
- Blood pressure: 124/82 mmHg
- Heart rate: 88 bpm
- Respiratory rate: 16/min
- JVP: Markedly elevated with prominent y descent
- Kussmaul sign: Positive (JVP rises with inspiration)
- Cardiovascular: High-pitched early diastolic sound (pericardial knock), no murmurs
- Abdomen: Distended with ascites (shifting dullness), hepatomegaly
- Extremities: 3+ pitting edema to thighs bilaterally
- Lungs: Clear (despite severe congestion - suggests pericardial not cardiac cause)

### Workup
- ECG: Low voltage, nonspecific ST-T changes
- Chest X-ray: Pericardial calcification (ring-like), normal cardiac silhouette
- CT chest: Thickened, calcified pericardium (4-6 mm)
- Echocardiography:
  - Septal bounce (respirophasic septal shift)
  - Preserved LV systolic function (EF 60%)
  - Mitral annular e' velocity: 12 cm/s (normal/elevated - unlike restrictive cardiomyopathy)
  - Respiratory variation in mitral inflow: 30%
  - Dilated IVC
- BNP: 180 pg/mL (mildly elevated - would be much higher in restrictive cardiomyopathy)
- Cardiac catheterization:
  - Elevated and equalized diastolic pressures in all chambers
  - "Square root sign" (rapid early filling, then plateau)
  - Respiratory discordance between RV and LV pressures

### Diagnosis
Constrictive Pericarditis (Post-tuberculous)

### Treatment
1. Diuretics for symptomatic relief of congestion (limited efficacy)
2. **Pericardiectomy** - definitive treatment
   - Surgical removal of the thickened, calcified pericardium
   - Best outcomes with earlier surgery before extensive calcification and myocardial atrophy
3. Preoperative optimization of nutritional status
4. Risk counseling: Operative mortality 5-15% depending on etiology and severity
5. Post-TB etiology has intermediate prognosis (better than radiation-induced)

### Physiological Principles Demonstrated
- **Constrictive physiology**: The thickened, rigid pericardium limits diastolic filling. Early filling is rapid (the ventricle is not stiff), but abruptly stops when the fixed pericardial volume is reached ("square root sign").
- **Kussmaul sign**: In constriction, the rigid pericardium prevents the normal inspiratory increase in right heart filling. Increased venous return backs up, raising JVP paradoxically.
- **Constriction vs. restriction differentiation**: In constriction, the myocardium is normal so the mitral annular velocity (e') is preserved. In restrictive cardiomyopathy, the stiff myocardium causes reduced e'. Both cause elevated filling pressures, but this key distinction guides management.
- **Ventricular interdependence**: In constriction, the total pericardial volume is fixed. Inspiration increases RV filling at the expense of LV filling, causing the septal bounce and respiratory variation in filling velocities.